Heat-resisting and fireproof concrete composition.



UNITED STATES Paw-212d August 30, 190- PATENT OFFICE.

HERBERT Ll DUNK. OF HOPEDALE. MASSACHUSEI rs. ASSIGXOR TO DRAPER COMPANY, OF i'lO'lEDAL-E, MASSACHL'SE'TS, A CORPO- RATION 0F MAINE.

HEAT-RESlSTING AND FIHEPROOF CONCRETE COMPOSITION.

SPECIFICATION forming part of Letters Patent No. 768,983,-d1tad August 30, 190-1 Auplicltion filed Karol: 7, 1904. Serill No. 196,974. (No pain-ins.)

To all who! if may concern:

Be itknown that I. H mun-arr L. DUNK, acitizenof the United States, rcsidingnt Hopedale, inthe countyof \Voa-cesterand State of Mass-ab chusctts, have invented an Improvement in lleat-liesisting and Fireproof Concrete (fumpositions, of which the following descri -ltion is a specification.

This invention has for its ol iject theproduction of a durable cheap concrete composition having high heat-resisting and fireproof properiies. suitable for various building, and constructional uses.

ihe composition can be used for floors in frmndries, forge-shops, or other places where hot metal is liable to come in contact with the tigers, and it is also valuable, on account of the cheapncss thereof and insensibilityto the action of high temperatures, as a iireprooiing material, especially in connection with reinforced concrete-steel building construction, in concrete buildings. and with hollow concrete building-stone.

My improved concrete composition is composed of cast-iron chips or turnings, sal-am moniac, Portland cement, sand, and water,

the ingredients being thoroughly mixed to form acohercnt homogeneous mass which can be molded, pressed, or otherwise made into di-sircd forms or shapes;

in preparing the composition l proceed as follows: Three barrels of cast-iron chips or turnings as they come from machinc-shops are spread upon a mixing board or platform in a thin layer--sa v abo'utan inch deep. One pint of sal-amniomac is then slfted over the layer of chips, and the latter are thoroughly 1 mixed together, after which one barrel of Portland cement. previously mixed dry with one barrel of clean sharp sand. is added toand thoroughly mixed with the chips. Then as much water as the mixture will take is added, and the whole is mixed well together to form a coherenthomogeneous mass, which is inolded or otherwise shaped, as desired, while in plastic condition. 0

in the course of my experiments I have i found that annealed cast-iron chips give the be t results, as they appear to lac more susceptible to the chemical action due to rent meat with the sal-anmmniac. The latter is used not only for itsevementing value. but be cause it makes the composition capable of standing wide extremes and sudden changxs of temperature \vith ut cracking or di integration. It is well known that oniinaryeoncrctc will not stand iiot iron 1.\ hen spilled thereon, as in a flan-dry, as it wiii lift and llillit. all like granite- Upon a gangway surfaced with about an inch of my improved concrete composition-a um UvoinClir-sof ordinam cemenbconcrcte a quantity of mo] Lcniron was poured and then r- 'mved. Water was then suddenly applied to 13:4: heated portion of the concrete,which was 5.1 1.0: that the wsier boiled for several minutes. with no resultant injury whatever to the concrete. Qvlindricai blocks of the concrete composition herein dwcrih-cd were heated to a white heat and then plunged into water without any cracking. disintegra tion. or any apparent injury whatever.

So far as regards strength, my improved concrete composition appears to be equal to the best concrete.

From numerous (851;!!!)(1 experiments which 1 have made the concrete composition has provedtobethorougialyefiicicntasa "veneering" or protective corering on expo ed surfaces in concrete and st el construction work to protect the same from heat and as a pm tective covering around steel beams, girders, columns, and other structural work. as well as for floors in cases where resistance to but is desired.

In using cast-iron chips it is to be presumed that the same are reasonably clean and free from oil and grease.

The proportions l have given for thcdiflerent ingredients are such as I have ound give highlysatisfaclory results: but these proportions may be varied somewhat without departing from the spirit and scope of my invcntion.

l Having described my invention, what I 

